Handling multiple schemas

[hlascelles]

We'd like to check multiple schemas in our DB. At present we are using the gem with great success in specs thus:

output = ActiveRecordDoctor::Tasks::UnindexedForeignKeys.new.run

However we can't see an easy way to move between schemas. Is that supported? Thanks!

[gregnavis]

@hlascelles, thank you for opening the issue. I'd like to clarify the meaning of "schema" here - do you mean something like a PostgreSQL schema? Or are you saying you're using two schema.rb at the same time?

[hlascelles]

This is for using with a Postgres DB with multiple (DB) schemas, but one schema.rb.

eg:

# We can test this:
public.customers
# But not this?
reporting.orders

[gregnavis]

@hlascelles, thanks for clarification. How did you set up Active Record for multiple schemas?

[hlascelles]

Almost everything is "normal" (eg the database.yaml), and then for a few models we change the table that ActiveRecord uses to look them up:

  class NormalModel < ApplicationRecord
    # This one is in `public`
  end

  class OrdersModel < ApplicationRecord
    # This one is in `audit`

    self.abstract_class = true

    class << self
      def inherited(subclass)
        super
        subclass.table_name = "audit.#{subclass.table_name}"
      end
    end
  end

That's it.

[krainboltgreene]

So we have a similar setup, except each model exists on two different schemas: Live and Sandbox.

[mediafinger]

Bumping this, as I just replaced redis with solid_cable - which will be a default in Rails 8.

I followed these steps (had to adjust a bit to make it work) https://github.com/rails/solid_cable?tab=readme-ov-file#installation to setup two databases (one only for actioncable messages). This triggered an error (see below) which I could avoid by adding SolidCable::Message to ignore_models. Adding solid_cable_messages to ignore_tables was not enough.

It would be sufficient for my use case to add an ignore_database statement to ignore all actioncable related stuff. But I assume for this to work the doctor would have to become aware of the two schemas.

ActiveRecord::StatementInvalid: PG::UndefinedTable: ERROR:  relation "solid_cable_messages" does not exist (ActiveRecord::StatementInvalid)
LINE 10:  WHERE a.attrelid = '"solid_cable_messages"'::regclass

[...]

Caused by:
PG::UndefinedTable: ERROR:  relation "solid_cable_messages" does not exist (PG::UndefinedTable)
LINE 10:  WHERE a.attrelid = '"solid_cable_messages"'::regclass
                             ^
[...]

SolidCable::Message references a non-existent table or view named solid_cable_messages

[apotapov]

Having a similar issue with solid_queue and schema_queue.rb. Seems like ignoring the tables doesn't help

global :ignore_tables, [
"solid_queue_blocked_executions",
"solid_queue_jobs",
"solid_queue_recurring_executions",
"solid_queue_claimed_executions",
"solid_queue_failed_executions",
"solid_queue_jobs",
"solid_queue_pauses",
"solid_queue_processes",
"solid_queue_ready_executions",
"solid_queue_recurring_executions",
"solid_queue_recurring_tasks",
"solid_queue_scheduled_executions",
"solid_queue_semaphores"
# ... any other tables you want to ignore
]